!! OMG, there’s a fly in it: Schiphol Urinals !!

I’m not sure if these are still at Schiphol Airport in Amsterdam, but each urinal in the men’s washroom had a fly painted in it. Apparently, if men see a fly in the urinal they aim for it, which helps keep the washroom clean.
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Growing up me and my brothers were so sloppy with pee that my mother started painting bullseyes in nail polish at the back of the toilet bowl. We’d even get a couple bucks as a reward when our piss had completely wiped off the polish.